This invention relates to improvements in training devices for athletes, and particularly to weighted devices adapted to be worn by the athlete to increase his running strength, speed and endurance.
To develop greater speed and endurance in running, an athlete should concern himself with strengthening the primary muscles of the thigh (quadriceps). These muscles are the power source for forward motion. An increase in thigh strength will produce a longer stride length and an ability to push through a given resistance more quickly, both of which increase the running speed of the athlete.
The relative degree of muscle strengthening which occurs during an athlete's training depends on the resistance which these muscles meet. The resistance imposed upon thigh muscles is the body weight of the athlete in the area above the thigh. Accordingly any increase in body weight by means of weighted training devices, to impose more resistance on these muscles and thereby strengthen them, must occur above the thigh muscles to be worked, i.e. above the waist area. For this reason ankle-mounted weighted training devices, such as that shown in U.S. Pat. No. 2,241,833, or thigh-mounted weighted training devices, such as that shown in U.S. Pat. No. 4,180,261, are inadequate for this purpose.
Conventional methods of weight training to strengthen these muscles (leg squats, leg presses, etc.), are confined movements that work a local group of muscles. As a result, an imbalance in muscle strength is created and the chance of injury increases. The hamstrings (opposing muscles of the quadriceps) are the muscles that sprinters commonly pull or tear when this imbalance is created.
What is needed therefore is a specialized training device that will strengthen the thigh muscles, as well as all of the other muscles that will be involved in running such as leg, ankle and foot muscles. This strengthening must be accomplished while the athlete is running to provide a balanced increase in muscle strength, and must be provided by increasing body weight, and thus muscle resistance, in the area above the waist.
While weighted training vests have, in the past, been used to impose increased muscle resistance above the waist and thereby strengthen the thigh muscles as well as the other muscles involved in running, such vests have suffered from several severe deficiencies which discourage most athletes from using them. A primary problem in this regard is that the weights carried by the vest bounce around dynamically while the athlete is running, thereby constituting a source of aggravation and distraction and destroying the athlete's rhythm and balance of movement. This disadvantage in itself would discourage must runners from using such weighted vests, and is even more of a drawback for specialized runners such as basketball players whose fine control of balance while running is especially critical. Tightening the vest on the body to the point where dynamic movement of the weights is minimized is impossible because such tightening would interfere with the runner's breathing. An exemplary weighted training vest of the type having such drawbacks is shown in British Pat. No. 5960 wherein a cloth vest contains metal weights. Although more recently cloth training vests having sand sewn into special pockets have been employed, such modern training vests continue to share the aforementioned drawbacks of dynamic weight movement which discourage their widespread use.
Muscle resistance provided by a weighted training vest should be variable in progressive and controlled increments as the athlete's muscle strength develops. Furthermore such incremental weight increases should be obtainable in a balanced fashion, such that the training device does not become appreciably heavier in the front than in the rear or heavier on one side than the other. These capabilities are also beyond those of conventional weighted training vests.